Question: Whose child is the son of Frederick William, the Elector of Brandenburg?
Paraphrase: Whose child is the child of Frederick William, the Voter of Brandenburg?
SPARQL (Wikidata): SELECT ?answer WHERE { wd:Q152727 wdt:P22 ?X . ?X wdt:P40 ?answer}
Answer: Frederick William, Margravine Hedwig Sophie of Brandenburg, Margravine Louise Charlotte of Brandenburg